#define TLV320AIC23ID1 (0x1a) // cs low
#define TLV320AIC23ID2 (0x1b) // cs high
-void aic23_power_up(void);
-void aic23_power_down(void);
+#ifdef CONFIG_SENSORS_TLV320AIC23
+extern void aic23_power_up(void);
+extern void aic23_power_down(void);
+#else
+static inline void aic23_power_up(void)
+{
+}
+
+static inline void aic23_power_down(void)
+{
+}
+#endif
#endif /* __ASM_ARCH_AIC23_H */